prompt = "\nHow old are you?"
prompt += "\nEnter 'quit' when you are finished. "
# 询问用户年龄，并指出票价
while True:
    age = input(prompt)
    if age == 'quit':
        break
    age = int(age)
    
    if age < 3:
        print("Free")
    elif 3 <= age < 12:
        print("10$")
    else:
        print("15$")
